Timken 78251D – 78537
Tapered Roller Bearings - TDI (Tapered Double Inner) Imperial
(BRAND)：TIMKEN
(Availability)：In Stock
Specifications
Series
78000
Cone Part Number
78251D
Cup Part Number
78537
Design Unit
Inch
Cage Material
Stamped Steel
Related Assembly Number(s)
78251D-90050
Dimensions
d - Bore
63.500 mm
D - Cup Outer Diameter
136.525 mm
B - Double Cone Width
65.989 mm
C - Cup Width
23.520 mm
T - Bearing Width across Cups
66.091 mm
Abutment and Fillet Dimensions
R - Cone Backface "To Clear" Radius1
2.300 mm
r - Cup Backface "To Clear" Radius2
3.30 mm
da - Cone Frontface Backing Diameter
79 mm
Db - Cup Backface Backing Diameter
115.06 mm
Ab - Cage-Cone Frontface Clearance
2 mm
Basic Load Ratings
C90 - Dynamic Radial Rating (One-Row, 90 million revolutions)3
44300 N
C1 - Dynamic Radial Rating (Two-Row, 1 million revolutions)4
298000 N
C90(2) - Dynamic Radial Rating (Two-Row, 90 million revolutions)5
77200 N
C6
65700 N
Factors
K - Factor7
0.67
e - ISO Factor8
0.87
Y1 - ISO Factor9
0.78
Y2 - ISO Factor10
1.16
G1 - Heat Generation Factor (Roller-Raceway)
62.6
G2 - Heat Generation Factor (Rib-Roller End)
19.1
Cg - Geometry Factor11
0.0884
